I think there are well paid jobs outside London... I'm on nearly 30k a year after graduating, will be up in the mid 40s as soon as I qualify and I've got a house with 2 double bedrooms for £120k, in good nick, with a big garden, new central heating and double glazing... the salary is lower but the cost of living is a hell of a lot better proportionally.
But, given you do want to live in London, that flat looks really nice - decent sized living area, 2 decent bedrooms and a third okay one. Think I'd be considering schools round there just for resale value and would probably want a proper structural survey, given it's been on the market for ages. Don't know about road noise. Do look st the energy rating/ask owners what their bills have been like as some flats like that seem to eat energy. If the library below shut and wasn't replaced with something else you'd have a very cold space underneath you.